This invention relates generally to facsimile transmissions of information visually displayed on a medium such as paper, and more specifically to the transmission of facsimile copies by interfacing standard facsimile units with high frequency single sideband radios. Standard facsimile machines (FAX) are now widely used to transmit copies of printed and pictorial information over telephone lines. The usual practice is to couple a FAX to a dedicated telephone line that provides two-way communication to all other FAXs which are likewise coupled through their own dedicated telephone lines. Other FAX systems are in use which transmit information over radio frequencies. However, all such systems known to applicant use duplex operation (one frequency is used for sending and another frequency for receiving).